Virial coefficients and demixing of athermal nonadditive mixtures
Abstract
We compute the fourth virial coefficient of a binary nonadditive hard-sphere mixture over a wide range of deviations from diameter additivity and size ratios. Hinging on this knowledge, we build up a expansion [B. Barboy and W. N. Gelbart, J. Chem. Phys. {\bf 71}, 3053 (1979)] in order to trace the fluid-fluid coexistence lines which we then compare with the available Gibbs-ensemble Monte Carlo data and with the estimates obtained through two refined integral-equation theories of the fluid state. We find that in a regime of moderately negative nonadditivity and largely asymmetric diameters, relevant to the modelling of sterically and electrostatically stabilized colloidal mixtures, the fluid-fluid critical point is unstable with respect to crystallization.
Cite
@article{arxiv.cond-mat/0703032,
title = {Virial coefficients and demixing of athermal nonadditive mixtures},
author = {G. Pellicane and F. Saija and C. Caccamo and P. V. Giaquinta},
journal= {arXiv preprint arXiv:cond-mat/0703032},
year = {2011}
}
Comments
28 pages, 9 figures, to appear in J. Phys. Chem. B